求值域y=x2-2x-3/x2-5x-6
<p>问题：求值域y=x2-2x-3/x2-5x-6<p>答案：↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">甘伟的回答：<div class="content-b">网友采纳 推荐用Δ判别式法：y=(x²-2x-3)/(x²-5x-6)x²-2x-3=x²y-5xy-6y(1-y)x²+(5y-2)x+(6y-3)=0因为关于x的方程有解；所以(5y-2)²-4(1-y)(6y-3)≥049y²-56y+16≥0(7y-4)²≥0y∈R原...
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